It’s best to ask your boat dealer or the original boat builder. However, they rarely have an answer, especially on older boats because they don’t know the condition of your platform. The best way to find out is to look at the specification of your dinghy or Jet Ski to find their weight and test that weight on your platform with some kind of ballast. Normally it’s no problem with the platform, it’s the weight impact at the stern that can cause problem.